1. Field of the Invention
Embodiments of the present invention generally relate to a downhole tool for debris removal.
2. Description of the Related Art
Wellbores are formed one section at a time with each section typically lined with a string of tubulars (casing or liner) which are cemented in place before a subsequent, smaller diameter length of wellbore is drilled. The cementing process consists of pumping a curable material down the wellbore and circulating it back up an annular area formed between the new tubular string and the earthen bore around it. When lower sections of tubulars are cemented, there is typically cement residue left at an upper end of the string where it can cure and interfere with later operations. Debris removal tools typically have extendable arms or blades and are run into the wellbore on a work string. Once remotely actuated, the tools are rotated and/or reciprocated in order to remove debris from an upper end of the newly cemented string and from an interior of the lager diameter tubular thereabove. Prior art debris removal tools are unreliable. In one instance, friction between the blades and the debris or the wellbore walls, especially in non-vertical wellbores, can cause at least one blade to prematurely retract while in use. In most cases, an operator at the surface of the well is unaware of the malfunction. In other cases, the tools are removed in an extended position, risking damage to a tubular string therearound as the work string and tool are rotated.
What is needed is a debris removal tool for use in a wellbore that is more reliable.